FT4232H datasheet(16/43 Pages) FTDI

16 / 43 page

Document No.: FT_000060

FT4232H QUAD HIGH SPEED USB TO MULTIPURPOSE UART/MPSSE IC

Datasheet Version 2.05

Clearance No.: FTDI#78

+1.8V LDO Regulator. The +1.8V LDO regulator generates the +1.8 volts for the core and the USB

transceiver cell. Its input (VREGIN) must be connected to a +3.3V external power source. It is also

recommended to add an external filtering capacitor to the VREGIN. There is no direct connection from the

+1.8V output (VREGOUT) and the internal functions of the FT4232H. The PCB must be routed to connect

VREGOUT to the pins that require the +1.8V including VREGIN.

UTMI PHY. The Universal Transceiver Macrocell Interface (UTMI) physical interface cell. This block handles

the Full speed / High Speed SERDES (serialise - deserialise) function for the USB TX/RX data. It also

provides the clocks for the rest of the chip. A 12 MHz crystal should be connected to the OSCI and OSCO

pins. A 12K Ohm resistor should be connected between REF and GND on the PCB.

The UTMI PHY functions include:

•

Supports 480 Mbit/s "High Speed" (HS)/ 12 Mbit/s “Full Speed” (FS), FS Only and "Low Speed"

(LS).

•

SYNC/EOP generation and checking.

•

Data and clock recovery from serial stream on the USB.

•

Bit-stuffing/unstuffing; bit stuff error detection.

•

Manages USB Resume, Wake Up and Suspend functions.

•

Single parallel data clock output with on-chip PLL to generate higher speed serial data clocks.

EEPROM Interface. When used without an external EEPROM the FT4232H defaults to a quad USB to an

asynchronous serial port device. Adding an external 93C46 (93C56 or 93C66) EEPROM allows each of the

chip’s channels to be independently configured as a serial UART (RS232 mode), bit-bang mode or fast serial

(opto isolation). The external EEPROM can also be used to customise the USB VID, PID, Serial Number,

Product Description Strings and Power Descriptor value of the FT4232H for OEM applications. Other

parameters controlled by the EEPROM include Remote Wake Up, Soft Pull Down on Power-Off and I/O pin

drive strength.

The EEPROM must be a 16 bit wide configuration such as a Microchip 93LC46B or equivalent capable of a

1Mbit/s clock rate at VCC = +3.00V to 3.6V. The EEPROM is programmable in-circuit over USB using a

utility program called MPROG available from FTDI’s web site (www.ftdichip.com). This allows a blank part

to be soldered onto the PCB and programmed as part of the manufacturing and test process.

If no EEPROM is connected (or the EEPROM is blank), the FT4232H will default to serial ports. The device

uses its built-in default VID (0403), PID (6011) Product Description and Power Descriptor Value. In this case,

the device will not have a serial number as part of the USB descriptor.

FT4232H Datasheet(PDF) 16 Page - Future Technology Devices International Ltd.